Three experiments were carried out to study the effects of α-chymotrypsin with gelatin on anti-sperm antibodies (ASAs) in rabbit's semen and fertilization rate. In the first experiment, all rabbits males (20 bucks) were tested for the presence of ASAs in seminal plasma. The secondexperiment, aimed to define the effect of different levels of α-chymotrypsin supplementation (0, 100, 200 and 400 mg/100ml extender) with gelatin in tris-based extender in presence ASAs on progressive sperm motility%, live and abnormal spermatozoa%. In the third experiment, does were inseminated with semen diluted in tris-based extender (1:3) as described in experiment II. Insemination was carried out using 80 does divided into five equal experimental groups (16 does/group) and inseminated artificially by diluted semen containing 50x106 spermatozoa. Kindling rate and litter size were calculated.
Results showed significant (P<0.05) decreases in progressive sperm motility, while sperm abnormalities and dead spermatozoa increased (P<0.05) in the ejaculates with ASAs - positive (titer>1/10) as compared with ASAs-negative ejaculates (titer<1/10). Semen ejaculates positive-ASAs supplemented with gelatin and α-chymotrypsin were exhibited ASAs titer 1/10 in seminal plasma that represents a significant change (P<0.05) compared with control group (C). Most amino acids were significantly (P<0.05) increased by the inclusion of gelatin alone or gelatin plus α-chymotrypsin. Supplementation of gelatin and α-chymotrypsin significantly (P<0.05) decreased ammonia in semen, ALT and AST activities in seminal plasma, TBARS concentration, sperm abnormalities, dead spermatozoa, glutathione and superoxide dismutase, while, increased percentages of progressive linear motility as compared to the control. Kindling rate was improved as compared with the control group. In addition, the total and live litter size and bunny weights at birth were considerably higher for supplemented groups α-chymotrypsin and gelatin than those of the control group. The levels of α-chymotrypsin 200 and 400 mg/100 ml extender with gelatin represented the same significant differences with other experimental groups.
In conclusion, supplementation of rabbit semen with gelatin and α- chymotrypsin not only enhanced the semen quality but it also improved anti-sperm antibodies status and reproductive performance.